Do ants make traps?

I remember, like Home Alone, when I was a little kid, that that that whole sequence was a great It's sort of expands to fill my whole childhood impression of what the movie was. And if you go back and watch it as an adult, it's kind of weird that it's only like fifteen or twenty minutes of the runtime in in Home Alone. Yeah, yeah, yeah, it does seem like that's the main thing I remember. Yeah, they the traps, the traps, and and certainly people feel certain nostalgia for them.

My heart swells at the thought of a nail going into Daniel Stearn's foot. Um. But but also, yeah, I remember other ones, like you know, Arnold Schwarzenegger builds a bunch of traps in Predator. Um and but like this wasn't just when I was a kid. It still works on me. I remember there was a sequence I just loved in the more recent horror movie It follows where the characters build a trap for the monster. Yeah, that's right.

They that is very they have a very, very much a kind of home alone's setup that they do there. Of course, it's not only the heroes that that have traps. I always love a good villain trap as well, especially the trap door ump. Trap door sequence is always a lot of fun. Um uh you know, be it something like in in Lynn Labyrinth. I love the trap when the trap door springs on our hero and that. But actually Tomorrow's Weird House Cinema also has a fun trap

door sequence. Uh oh yeah, so look forward to that. Well yeah, on the side of the protagonists getting through traps set for them. Another one of my favorite movie sequences as a child was the beginning of Raiders the Lost Art. Oh yeah, and when Indians going through all the traps. Something about it is just like deep in the brain, it's very satisfying. Wall to wall traps. Yeah,

that's that's a great sequence as well. Um, and all of these are great sequences in spite of the fact that when you when you can, when you really think long and hard about any of these scenarios, uh, you know, the cracks definitely show would would all of these traps still be working in this ancient ruin that Indiana Jones finds himself in. I don't know, it's it's a hard argument to make their right, How did the spring trap operate by you sticking your hand through a shaft of

light when it was made like thousands of years ago? Yeah? Or you know, if it's duke and predator, like, how does he um? How does he make this super powerful calm pound bow just in the space of a few hours on an afternoon in the jungle? That's just standard survival training and all these other various ewok traps that he builds didn't didn't you go to that camp? Did I build a bow like that at a camp? Now? I think we sharpened sticks, you know, that would be

that would be more believable. Right, he makes a spear to battle, that's the way there. Yeah, but you know, I think it probably speaks volumes for humans to be you know, to be saying all of this about traps, and especially about you know, loving these cinematic treatments of traps, because because what are traps? Ultimately, very broadly speaking, they're clever, tactical and or technological innovations that level the playing field

against predators, against prey, and even against fellow humans. Traps are the sort of things that humans have been up to since prehistory. So of course we love traps, and of course we admire things like traps that we find another species. Right, So today we're going to be focusing on some allegations of insects with the ability to build traps, specifically ants that do things that may in fact be

biological evolutions that allow them to trap prey. Uh. Now, there are some other animals that I think we could say more more clearly and and famously create traps. I think the obvious example here would be spiders. Yes, yes, spiders are the trap builders par excellence. Uh. You know, there are no finer trap builders in the animal kingdom. Maybe you could make a case for human beings, um,

but personally I'm not in favor of that. I think, you know, well, building spiders especially are just such highly evolved trap masters. Every detail of their anatomy and behavior enhances their trapping ability, and the trap is very much an extension of their own bodies in so many ways. And we've covered this, and we've covered spiders in general numerous times in the show before, and we'll likely keep coming back to them. But yeah, that the spider, the

spider is the trap maker. There's nothing else that the spider really does. Um in anything else it does, the web building spider is going to do in close proximity to the web that it has built. Yeah. Another example that's come up before, I think in our Sarlac episodes

was the ant lion. Yes, yeah, uh. This is a case where we have predatory larvae that in some species of antline anyway, set up at the bottom of sand pits that they dig, ready to lash out at anything that disturbs their grains and you know, ventures down into the trap. Um. Again, not all ant lion species dig trap pits, but some of the most famous ones do. I remember. One of the great things we learned about the ant lion was that, like you say, the it

is the ones that make traps. It is just the larval period of their lifespan, their life cycle that they make the traps. Then they later metamorphos into into another form. But while they're in that larval stage, I think at least some of them never poop. Oh yeah, catching ants and eating them and just like waiting, and it's like if you had to wait until you turned eighteen to poop. We'll go back and listen to that Sarlac episode if

you'd like to hear more about the ant lion. There's also um the species of creature known as the worm lion, and this is this is unrelated to the ant lion. It's just a matter of convergent evolution that ends up utilizing largely the exact same method again when it's a larva. Uh though the pit itself in this case is generated via site a slightly different method, so it digs its pit in a slightly different method, but it's still consumes

its prey in the same manner. But for me, at least, if you ask me to make a list of non human animals that make traps, I could obviously go spiders. I would have thought of the ant lion, maybe by association the worm lion. But there before I was reading up for this episode, I think I would have drawn on a blank I wouldn't know what to go to next. Yeah, and part of it comes down to just how are you going to going to define a trap? Uh? For example,

here's here's an interesting potential example. Uh. We can discuss that I read across read read about when I was reading Gilbert Wald Bowlers How Not to Be Eaten, which which is largely about insects, but there's a part where the author is discussing the burrowing owl. So these are small birds native to the Great Plains in southern Florida. Um, I think they're about the size of a robin. I'm

to understand that. You know, they're small, little little guys, but they make their home in burrows that they did themselves. And one of the interesting things that they do in addition to this, if this wasn't you know interesting enough already, is the burrowing owl will scatter horse or cow dung around the entrance to their burrows. And in you know, times before European contact, this would have probably been bison dung.

And the dung does seem to be important because if if researchers remove the dung from the vicinity, the birds will just the bird will just go out and obtain more dung and place it in the vicinity. So it's it seems to be doing this intentionally. The theory is that they place the dung to bait dung beetles, So they put the dung out dung beetles come, And indeed, researchers have been able to tell that the owls eat ten times more dung beetles than usual when the dung

is out. Well, this will in fact mirror one of the two examples of potential aunt trap making that I want to talk about later. Yeah, I mean it's but but this is a great example. It's certainly clever. I like it. But it kind of forces us to ask the question of a trap, like what is a trap? Is just merely baiting a trap? Um? That is a good question, Yeah, because and um, how much does the trap structure have to be separate from your body in

order on as a as a constructed trap? And how much does it have to how much work does it have to do for you? Yeah? And at what point does an animal's behavior stop being a trap and just become sneaky behavior, sneaky tactics, or or simply ambush predation.

Because obviously there are plenty of examples of ambush predators on land and in the sea, and these include everything from well, the trap door spider for one, which I think is is definitely a case of of trap building because it's it's an ambush predator, but it builds a silk hinge trap door to aid in those ambushes, right, so the trapdoor hides it. I think you could count that as like infrastructure necessary to constitute a trap. Yeah, yeah,

I think that, Yeah, definitely with the trapdoor spider. But then you also have just various camouflage predators, including things like frog fish, praying mantis is, chameleons, and more, which are not building anything. They're not altering their environment, but they've evolved to look like a part of or environment. Uh, and they have you know, often tremendous abilities of camouflage that enable them to quickly ambush something that they want

to eat. Okay, that probably doesn't that doesn't really seem like a trap to me, because they're just evolved to look that way and they do the actual hunting themselves, right. And then of course we have various birds and cats and big cats even, uh that are just very stealthy that are just very good at not being observed by

the things they want to kill. So I was reading a little bit about this in Douglas j Imland's excellent book Animal Weapons that have Referenced on the Show before, and he points out that creatures such as this generally depend on quote, a quick strike weapon that immediately incapacitates

its victim. And of course these bioweapons might be enhanced by special features, such as in various deep sea ambush predators a bioluminescent lure, which again is not something they have created or engineered out of their environment, but it is a part of their body. So when we come back of this idea that what needs to be something that's built, it needs to be something that's engineered, or just a whole dug in the in the ground. Even um, we come back to that same question, well, why don't

we find more of this? And I actually found an interesting paper title out there, why are pitfall Traps so rare in the natural World? By G. D Ruxton and M. H. Hansel, And it appeared in Evolutionary Ecology in two thousand and nine.

Interesting question. Yeah, So the authors here point out that in order to lay a trap, you generally need either advanced cognitive powers as with humans obviously, or you need specialists self secreted materials as with spiders and catis fly larvae thing which the Catasta catass fly larvae use that their their secretions to create a net like even meshed trap like a silk um trap in order to like

filter catch their prey. That makes sense. So humans can create all kinds of traps because we have of you know, cognitive powers that allow us to imagine what could be done. How you know, other materials in the environment could be repurposed to uh, to passively ensnare or kill prey, animals and spiders and stuff. That that's just the trap you could almost say, is a part of their body. Even

though the web is a built thing. They're evolved to secrete the silk for the web out of their bodies, and they have very instinctually driven behaviors for how they extrude that silk where and in what patterns. Right, So Ruxton enhansl here ultimately point out that, okay, we have the ant lion though, and of course the worm lion. Uh, these are exceptions to the rule. Um they make use of a pitfall trap, and so the authors asked, why is this basic tactic not more common in the animal world?

How hard is it, after all to dig a hole? They're easy, they're cheap um, And yet you don't see this technique used by virtually anything outside of and of some ant lions and worm lions. Apparently, the lack of more pitfall traps in nature was something of a mystery, or and remains something of a mystery. Yeah, that that is interesting, Okay, so I it took me a second

to get the distinction they're making. But they're saying that the ant lion and the wormline would be kind of an outlier because they don't have complex intelligence and imagination like humans, so they're not inventing traps with cognitive powers. But they also don't secrete a material that constitutes the

basis of the trap like a spider. They're literally just building a trap out of the dead environment around of them by digging a conically shaped hole in such a pattern that that ants get stuck in it when they fall down the side. But and and why is that so rare, because it would seem like that that should be a strategy that lots of animals could easily employ. Right, Yeah, again, holes are ultimately easy to make, low energy? Why not? Why? Why? Why is? Why is this cat not making a hole

and using that as part of its hunting tactics? So what? What? What are their thoughts on this? Like, why would why wouldn't we see this more often? Well, they proposed to speculative reasons for the lack of pitfall traps in nature. The first one is pitfall traps may require a specialist micro habitat. In other words, you can't do this just anywhere.

Conditions have to be just right, uh, such as you know, we can look at the ant lions, they have to be kind of sandy conditions, you know, you have to have that kind of granular environment. Um. So it's the kind of tactic that a potential trap builder would not necessarily be able to employ all over the place. You would have to depend on us, again, on a specialist

micro habitat. I think I recall from our Starlac episode where we had a segment about the ant lion that they needed the grains of soil to be of a particular size, like the sandy grains above or below a certain diameter threshold would not work very well for making

the traps. Yeah. Yeah. Now, the second point is that with the ant lion in particular, the trap targets small prey, and since they may be more functionally tied to their trapped and spiders are traps of this nature, could serve as like basically a major bull's eye for potential predators. And indeed the main predators of ant lions and worm lions are birds who know what to look for. That's

a really good point. So by building a trap and then sitting in it and waiting for your prey to fall in, you were also usually going to be making a structure that makes it easy for things that want to eat you too, I defind where you are. You know, they don't have to look too hard because you've made a big hole in the ground, right and uh, and spiders just have a little more leeway with the situation. Now, I should point out Hansel also wrote an entire book

which I'm gonna reference here in a minute. He spends a lot of time in that book talking about spiders and how you know, some sometimes spider webs are very visible, h in other times they're not, and how that plays into the you know, the ultimately kind of complex relationship between spiders and uh, and the creatures that would eat spiders. Um. But but just thinking about this as the trap being this conspicuous thing. This we actually see this in a

lot of our fantastic trap fiction. You know that moment when the target of the clever cinematic trap, especially if it's laid by the protagonists. Uh, the the enemy almost sets it off, right, like the predator almost triggers the trip line you've prepared. But then something happens right the uh, the monster deduces that the trap is there, or it

suspects that something is a little off. Oh and maybe even the presence of a trap is how the hero knows that they have stumbled across the bad guys hideout. Yeah yeah, um. It even reminds me a bit of our recent weird house selection the Lift. This was the killer elevator movie. Uh, the killer elevator in this or I guess you were more specifically the weird bio brain that's been installed in the elevator shaft to power these elevators.

It's kind of an obligate trap predator. Um. But it's so tied to that in ironment that it's a little tricky. Like it it's not able to pull off every kill, and it's eventually destroyed by prey that is too clever for it. Brilliant analogy. This this is true. The killer Elevator is an obligate trap predator. I also have to point out, speaking of the Star Lack, is that recent Mandalorian episodes have also, you know, sort of played with

this idea. Yeah. Yeah, the Mighty Star, like the Star looks pretty impressive, but they make it clear that even these great trap predators can be a consumed by the mighty crate dragon that lives in the deserts of Tate wein uh, so knowing you're there being you know, this identifiable organism in the sand that can have a huge

downside to it. Now, I was trying to think of counterpoints to the idea that okay, so, uh sitting at the bottom of a pitfall trap and waiting for prey to fall into you and then eating that that makes

you vulnerable to two predators that want to find you. Well, well, what if you just make pitfall traps and then you go away and then you you know, leave them there and then come act like a human hunter might do you know, leave a trap out in the woods and then come and see what it collected, lobster traps or something.

But but I can see downsides to that as well, because if it's just a pit trap, you could imagine that, well, something might fall in there, but then something else might eat it before you get to it, um so or it might you know, if you have to make these all over the place, you might spend a lot of energy going around from one to the other. So is

that really all that much better than just hunting? Well, and then it kind of comes back to this idea that that the trap laid by an animal, especially um still requires the lethal mechanism, and in the case of the ant line, the lethal lethal mechanism is itself. It is still essentially uh an ambush predator like again, like Emlyn says, quote a quick strike weapon that immediately incapacitates its victim. That, yeah, that I can't believe. I didn't

think of that. That's of course a good point. You have to find a way to kill the prey. So I mentioned that that Hanzel has a has a whole book that deals with with with some of this a little bit, but just sort of the broader picture of animals building things it's titled animal architecture, and I was reading through this a bit. He contends that we're not looking at traps when we're looking at cases of an animal baiting another animal, because traps are a kind of

subset of animal architecture, an engineered space that aids and capture. Okay, so, by his metric here, what the burrowing owl does by by leaving dung out around its nest and having this attract insects to it, that would not count as a trap because it is not a structure that in any way aids and capture. It just attracts prey to a site. Oh, by the way, I want to also speak speaking of the burrowing owl again, I want to throw in that that while some burrowing owls do build their own burrows,

they're also burrowing owls that acquire the burrows of other creatures. Anyway, I want to read this quote from Hansel here. I think he puts it rather well, uh, concerning the animal architecture and traps quote. Whereas a house can just be a barrier between the builder and the outside world, a trap has a dynamic relationship between itself and the prey. The prey needs to approach the trap in a particular orientation to it, and then needs to be restrained by it.

Traps are therefore more complex than homes and need to be more precisely engineered, and then he goes on to point out the quote among the vertebrates, trap builders were apparently absent until the recent history of man. Now he cites human mental capacity once more for the construction of such traps, noting quote, Virtually all non human trap builders use self secreted materials, and the capture principle they adopt

is the net. The exceptions are simple in design and operation, as well as rare, and then he goes on to specifically mentioned ant lions, uh, worm lions um and larval dip tira. But anyway, a large takeaway here is that trap building is not as widespread in the animal kingdom as you might expect. Humans make a lot of traps.

There are some very specialized animals, especially some invertebrates, that use traps made of materials that they secrete from their own bodies, but generally, trap building is not a very widespread hunting strategy among animals of planet Earth, in which case it would be very interesting to find examples of animals such as ants that make traps in order to

get their nutrition. And I guess that's a good segue to what I to the main focus of today's episode, which was a couple of examples I came across of ants that do something that could be interpreted as building traps as a hunting strategy. Yeah, and I mean it it would make sense that we might find something like this in the ant world because ants are masters of construction there, they alter their environment. They're capable of of

practicing um agriculture. Uh. They as we've discussed in previous episode the show, Uh, they engage in complex conflicts that we may might well compare to warfare. They can solve problems there. I mean, the list goes on and on. Ants are amazing um as as of course, as as the now lady oh Wilson was fond of reminding us, Um, you know, ants, there are incredible creatures that we've We've covered them numerous times in the show before we're covering today,

and I'm sure we'll cover them again exactly. So the first example I want to talk about I found so interesting, and this one also has some interesting differences in interpretations that came across. But just to to start with the basic report. I was reading about this in a paper published in Nature in the year two thousand five by A. Land Jean Pascal, Jean Solano, Julian Iralay, Bruno Corbara, and Jerome Oriville called arboreal ants build traps to capture prey uh.

And also as a supplement to the paper in Nature, I was reading a summary feature that was also in Nature by Nourrell Tawie published in April two thousand five, called Amazonian ants ambush prey. So here's the deal. There's a plant in the Amazon called her tell Phisophora or maybe Physophora p h y s O p h O r A. I'm gonna try to say phiz opera. So these here here teleplants. Plants in this genus are woody

trees or shrubs. I've seen them called both trees and shrubs, but there if you're trying to picture them as a tree, you should be imagining a small tree. So woody stems but not like you know, sky high. Plants in this genus are found in the tropics across multiple continents, but their diversity is concentrated around the Amazon, and they typically have flowers that are pollinated by butterflies. And this one species in particular here tell a phiz offerra, is what

the authors of the paper call an ant plant. This is a plant species that is known to have a specific biological relationship with a species of ant uh and these can be found throughout the world. They're they're very common mutualis ums or you know, various kinds of symbiotic

relationships between ant colonies and the trees or plants they inhabit. Now, this plant in particular has a relationship with the arboreal ant alomeras decim articulatus, and they live on the body of the plant, forming colony centers in what the authors of the paper called leaf pouches. They're these little bull looking things that can usually be found at the places where the branches split into leaves. They look like the

it's kind of hard to describe. They're just these little like green lobes or orbs, and apparently the ants like to get inside those and make nests in there. Now all already, one of the things that's that I'm reminded of is the idea of like a specialist micro habitat. And if you have a situation where a plant is is the home to the ants that they have this uh, this this ant plant relationship in place. Um, you know

that the plant itself is kind of the environment. It's kind of the micro habitat that the the ant is the master of. That's exactly right. But the interesting thing is, of course ants being builders, some ants will form complex, you know, dugout colonies in the ground or or other types of interesting engineered environments. They can also engineer the micro habitat of the surface of a plant, and that's

what we're gonna be talking about in this case. So uh oh, and I should say that the colonies that were looked at in this two thousand five paper were from French guyana in in northern South America. But so, what you find in these plants that are occupied by their by their familiar ant species is that along the stems of the host plant, the ants will build what the authors of this paper called galleried structures, or sometimes

they just say galleries. It's kind of hard to describe exactly what this is, but imagine a kind of platform built out over the surface of the stem of the plant, and it's a platform that the ants can crawl underneath, and then this platform has a kind of spongy texture, almost as if it's or honeycomb texture. It's aligned with all these holes in the platform that the ants can crawl in and out through. Generally, generally the holes are just slightly larger than the diameter of one of the

worker ants heads. So they're these platforms raised above the stem of the plant. Ants crawl underneath them, but then crawl up and up and down in and out through the holes in the platform. Yeah, it is kind of difficult to describe it because it is so different from something that that humans would for the most part build, you know, the um you know, by virtue of the ants being far more mobile and sort of living in a in a more three dimensional space than human beings

tend to. By the way, these are great to look up, probably unless you suffer from trip to phobia, in which case stay far away if you're if you're freaked out by things like lotus pods, uh and um and random holes and things, yeah, you might you might want to avoid this particular Google image search. Now, how do the ants build these galleries, Well, they apparently make them by cutting off tricombs from the stems of the plant. Tricombs is a word that comes from the Greek word for hairs.

These are small, little fibery appendages that poke out from the surface of a plant. You've probably seen lots of plants before that have little hairy things all over the stem or the leaves. Those are tricombs, and they do look a lot like hairs. So the worker ants will move along the stem of a of a Hairtella Fhizophora plant, clearing away the tricombs and then just to read from the language used in the paper here quote, then using

uncut tricombs as pillars. They build the galleries vault by binding cut tricombs together with a compound that they regurgitate later. This structure is reinforced by the mycelium of a complex of sooty mold species that has been manipulated by the ants. Fungal growth starts around the holes and then spreads rapidly to the rest of the structure. So I think you

you heard that right. So these ants build their galleries along the stem of the plant by cutting the hairs off of the plant where they live, then using those hairs as building materials along with their own barf as a kind of mortar, and then holding everything together by seating it with mold or fungus that they farm, So they have a kind of agricultural project. Were farming fungal rebar that they used to reinforce the galleries that they build. And in quotes given to the press, I've seen the

authors of the study compare this composite material to fiberglass. Wow. Yeah, that does seem like a good comparison. Oh man, I mean, it's just so amazing that it's not just like this physical um act, but they're actually have seating it with uh, with this this mold. Oh man, they're kind of they're they're building it, but they're also kind of growing it. It's amazing, and and they tend to it as it grows.

So I wanted to read another section from the study where they talk about the evidence that the ants are actively tending the fungus as it reinforces these structures. They say, quote, we noted that the stems of thirty four young seedlings, which had not yet developed leaf pouches, did not bear fungus. Nine saplings raised in a greenhouse in the absence of Alamira's that's the the ants di developed leaf pouches, but

never bore fungus. However, fifteen saplings raised in the presence of ants bore my celia, whose development was limited to the galleries. When we eliminated the associated ants from five of the fifteen, the fungus on the galleries grew into a disorganized structure, and none of the nine new stems that developed bore any fungus at all. Okay, so the fungus is only showing up on the plant when the

ants are there on the plant. And if you take the ants away from the plant after they've been using the fungus to reinforce their their galleries, the fungus kind of grows out of control and what they call a disorganized structure. But with the ants still there, it stays nice and tightly formed around the holes in the galleries.

So they're they're tending their garden. It's like a living and I don't know, it's like if you have to have maintenance workers constantly sort of gardening and tending to the fungus that held up your skyscrapers. But but but here's where we start getting to the trapping. So the authors of this study say that they noticed that sometimes larger insects would become immobilized on the surface of the galleries.

So you got these these spongy surfaces, ants crawling underneath them, and sometimes like a locust or a butterfly, some bigger insect lands on the gallery and then it gets stuck. What's going on here, Well, they started to investigate whether the galleries could be functioning as a type of trap. And here's what they say about how the ambush works quote. Our observations revealed that Alomiris workers hide in the galleries with their heads just under the holes, mandibles wide open,

seemingly waiting for an insect to land. To kill the insect, they grasp its free legs, antenna, or wings and move in and out of the holes in opposite directions until the prey is progressively stretched against the gallery and swarms of workers can sting it the and then slide the prey over the top of the gallery, again moving in and out of the holes, but this time in the same direction. They move it slowly towards a leaf pouch

where they carve it up. Oh, and then once they get to one of these population centers of the colony, you know, these these nests, nest sites in the leaf pouches. Uh. They tend to feed bits of protein from the insect to their young. Well yeah, this is amazing and suitably brutal for the world of ants. So this this, this larger creature lands or walks on to the structure. Um, you know, they're reaching out of holes to pull it straight down and then they transfer it to a place

where they can carve it up. Right. Uh So yeah, there's no sentimentality in the world of ants. They're just like, okay, this is edible. It's time to get to butcher in. But anyway, these observations reveal this this fascinating three way interaction between the plant, the fungus, and the ant all sort of ving together in this this this uh three way life cycle essentially that apparently serves the purpose of creating a trap to get larger insects. You know these stuff.

Oh I don't think I mentioned, but the Alamira's decim articulatus ants are very small. It's a it's a structure that allows these tiny ants apparently to capture kill and butcher much much larger prey. All right, And of course the plant, out of all of this gets some slight mutilation from the ants, but is protected from larger insects that would otherwise uh not on it and do more harm to it than just you know, creating an interesting lattice work out of its body. Presumably, I mean, I

think often there is such a relationship going on. The insect also provides a benefit to the plant somehow, uh though in the sources I was reading, it wasn't clear to me exactly if it's known what what the major benefit provided by the ants is. But I would guess that's right, that they're probably protecting the plant from from herbivore large herbivore insects that would chew it sleeves down

or something. But I don't know for sure. I gotta admit r And then of course we also have to do always realize that in the natural world the line between parasitism and symbiosis is sometimes a bit thin. These are not relationships that are governed by strict contracts, so you might see a little bit of push and pull over the course of evolutionary history. Yeah, ants will take whatever they can get, right, so you be careful about

entering into a bargain with with with the ants. But on the other side of all this, I wanted to come back on it because I found a book where the trap interpretation of these structures has been challenged. And in fact, this book was by somebody who's come up on the on I think episodes we did about ants last year, the biologist Mark W. Moffatt. Yes, yes, yeah, so he has a book called Adventures among Ants that was that came out in two thousand ten University of

California Press. And in this book I found a section where Moffatt argues that the trap interpretation of these structures built by Alamiras desim articulatus is in fact a misinterpretation. Now I'm not sure he's right about this, but I do want to explain what he claims. So it's a

bit of background. In In the section of the book directly preceding this, Moffatt has been talking about his observations of various species of army ants on rating parties to forage for food and also on defensive patrols to protect the colony and the rating column from threats. And one of his observations in this in this preceding section is how difficult it is sometimes to tell the difference between

these two behaviors and how easily one bleeds into the other. So, according to de Mofat, for most army ants, their defensive attacks on a creature that is received to be threatening, the rating column can quickly turn into a foraging rate in itself. So if the threat is killed, it is pretty much immediately chopped up into pieces and carried away as food. So it's kind of like if you imagine every monster movie ended with the heroes butchering and eating

the monster after they finally defeated it. Well, we do see that sometimes. In fact that that occurs in the Mandalorian but um in the case of the Great Dragon. But but yeah, we should see more more consumption of the drag of the dragons and monsters and so forth. Use every part of the monster be responsible. Well, I don't know, I mean that's you know, our humans are different than ants. I mean, ants are not going to

let anything go to waste. Humans after you fought a monster, you might just want to have nothing to do with it. To each species their own. But anyway, so from here, Moffatt moves on to describing the aunt I've been talking about Elmira's decim articulatus, and he's describing its living situation. The one distinction he makes I couldn't find out what

was what was the disconnect here? But he said, you remember how I said that the ants build these gallery structures out of tricombs cut from the plants, a little plant hairs, mixed with their own regurgitation or vomit, and then uh and then lined with the mycelium of the fungus that they cultivate. Moffatt describes it the same way,

but he mentions feces rather than vomit. And I don't know who's right there, but anyway, Moffatt gives a few reasons that he had doubts about the generally accepted interpretation of this structure as a trap, specifically as a trap, because he says a trap implies that, for example, a locust landing on the ant gallery would not have landed

there if it saw the ants. The trap would be performing the function of hiding the ants, so you know, they're hidden beneath the vault of the gallery, so that the prey insect feels it's safe enough to land and then they jump out and grab it. Okay, this would be in keeping with say the trapdoors Fighter. Uh, would probably be a great example of this. Yeah, yeah, I think that's that's comparable. That that's how it would function

as a trap. But Moffatt writes that he thinks this is unlikely because he doubts that grasshoppers would really be able to notice the tiny workers of this ant species anyway, quote, particularly in mid leap, or that they would be able to change course in mid leap after noticing them. So he was a little iffy on that. He's like, I'm not sure that the trap would really serve much purpose if it's supposed to be hiding the ants from the prey animal, because these are these are insects that are

much larger than the ants anyway. Right, So he's saying, basically, he's saying like this might be if this was a trap, which he doesn't think it is. Uh, it would be a preposterous trap. Uh, an unnecessary trap. And while again we love unnecessarily complex and preposterous traps in our cinema, we're not talking about cinema here. We're talking about evolution and full of sufficient yeah. Yeah, and things need to be ruthlessly efficient and if it's not ruthlessly efficient. Uh,

it is going to change or go away. But anyway, those are his suspicions, so he decided to put them to the test. So he tells a story of that that he was studying colonies of this ant in the wild in Ecuador, and he put together a test to

interrogate the trap interpretation. So to read from the section of Mofet's book where he describes this test, he says, quote, I hung a mosquito net over a plant with a thriving Alamira's colony, added a hundred grasshoppers and katie DIDs and sat inside for the next five mornings, an unusual case of using a mosquito net to keep insects in

instead of out. Even after the grasshoppers settled down, they were indiscriminate in their movements, hopping from where the ants hid under the structures to where aunts strolled in full view, to where there were no ants at all. When they landed among the ants, even on the structures that got away on hurt. Certainly, if the structures served as traps,

they were inefficient ones. So he's saying in his observations here, he's seeing very little correlation between the structures and the hunting behaviors of the ants or the behaviors of the prey insects, So what purpose does he believe the galleries are serving. Well, he points out that the galleries tend to run along the stems of the tree, connecting each nest pouch to to another nest pouch, and they quote contain a highway of workers commuting from nest to nest.

And then he points out that other insects, including other ant species, do sometimes build various types of physical covers over their trails, which are generally interpreted to be defensive in nature. For example, some marauder and driver ants have been observed to build soil covers over their trails. So could that be what's going on in this case? Could these galleries that the ants build at actually be defensive

in nature? Another strike here, According to Moffatt, he observed that the workers at his study site did not actually sit and wait at the holes in these galleries, as you might expect them to do if they were planning an ambush. He says that when conditions were normal, so like if the colony is not in an agitated state, things are just sort of going along normally most of the gaps in the gallery structures were unoccupied, but he says this changed when there appeared to be some kind

of threat to the colony. Quote, after a day of pulling grasshoppers from my hair, I noticed interlopers of another ant, a species of fidoli or big headed ant, climbing the plant to pin down a wounded grasshopper missed by the Elamiras. Upon the arrival of the fidoli ants, the Alamiris workers began to guard each of the several dozen entrances to

their arcade. And that's the arcade, is what he's calling the things that the other authors called the galleries, the several dozen entrances to their arcade nearest the commotion caused by the intruders. These guards, aided by nest mates roaming the arcade surface, also caught and killed one fight ali

and carried it off. So, based on these observations, Moffatt argues that the galleries are more likely defensive to protect trails of workers moving from one leaf pouch to the other, but that when something attacks or threatens the colony, the workers quickly shift their behavior from travel to defense, and then they occupy the holes and start biting violently at

anything that comes near. And of course, if they are able to immobilize an attacker, or not necessarily an attacker, if they're able to immobilize whatever it is that put them on the defense, they immediately shift rolls again and turn that threat into food and begin butchering it for the colony again, to to cook the monster, so speak. So we might be better to think of these as defensive fortifications, kind of like to use like a medieval

castle or fortress scenario. It's kind of like the various uh crinulations and murder holes and uh and and aero slits, except with the with the with the added point that in this case the occupants of the castle or fortress would eat those that they killed defending it. Right, That's what Moffatt argues, uh And So to to finish up his section, he says in the end quote in this

way the organization of a super organism. He's referring to ants there because I think you can make the argument that, you know, an ant colony might be best understood as one organism rather than many. It is a super organism composed of many different bodies, he says it quote can be more responsive than the tissues in a body. Trail bound workers can shift seamlessly in their behavior from transport

to protection to predation. It's as if one's liver could change function when the heart is incapacitated and pump blood. So obviously I don't know who's right here. Moffatt's book

is more than ten years old at this point. Uh, And most of the things I read about this ant species, alameirastsim articulatas still described the galleries as ambush traps and and I'm not sure which interpretation is correct, but I do think either way, Moffatt makes a very interesting point about the fluidity of function when it comes to ant behavior. How you know one moment's enemy is the next moment's lunch, right, Yeah? Like that, Like the ant colony is not just trying

to do one thing. Um, it has a lot of objectives and it has again this fluidity of function. Whereas it's it's far easier to look at at a web building spider and know what's up. You know that the web is it's uh is its purpose, The web is kind of its soul, uh, And there's no question about why it constructed. The web I guess also that this raises another question about what counts as a quote trap, because assuming for a second that Moffatt's interpretation is correct.

I don't know it is, but if he's right that these structures are primarily to defend the ant trails, but then when some when a threat presents itself, they turn around and use the holes in the galleries as murder holes and then eat whatever they can immobilize, does that count as a trap? Like? How how specialized does a structure have to be for the purpose of catching prey in order to be thought of as a trap, Because you can imagine other examples where an animal builds a

structure that's primarily defensive in some way. It's more like the home from the example you talked about at the beginning in that book. You know it's a barrier between you and the outside world. Yet it has some kind of feature that like another animal or something could get stuck on or something. You know, it's somehow allows you to sometimes opportunistically harvest from the structure and then eat from it. And does that count as a trap? Now?

I haven't seen this movie in a very long time, but but I think there might be something comparable and Home Alone too, am I oh lost in New York, the one with Tim Curry. What Tim Curry is in that one? I think he plays a he plays a snooty bell hop or something that sounds about right. Yeah, but yeah, I think the uh Actually, we were trying to figure what this out, what this was, and Seth

just chimed in to let us know he was right. Um. The house where he builds the traps in Home Alone two is a house that's like under renovation, so it already has featured Like all the traps don't have to be imagined from scratch. There are already features of the house. I don't remember exactly what they are, but there are

things that are dangerous about it already. Okay, yeah, but I wanted to talk about my second example of ants potentially doing something that you could interpret as a trap, and this one also involves using foreign materials around the nest. So the second example was described in a paper that I was reading published in twenty nineteen in the journal Ecological Entomology by A. Nacio Gomez Diego, Santiago Ricardo Campos, and Geraldo Vasconcelos. It was called why do Fight Ali?

Oxyops ants place feathers around their nests. And I also got some additional information from reading an article about the study published in Scientific American by Joshua rap Learn in November twenty nineteen. But here's the deal. So there is this species of ant called fidoli oxyops. We were already talking about some fidoli ants in the last example because the remember the fidoli ants invaded the tree and then they got kind of butchered by the by the Alamira's aunts.

But fidoli answer a genus known as the big head ants, and this species, in particular, Fidoli oxyops, is native to South American savannahs. So these should be you know, grasslands ants. Sometimes they appear to do something pretty we beard. They collect feathers and place them around the entrance of their nests. So if you imagine the nest is buried, the entrance is basically a hole in the ground, and then you might just find feathers all around the whole, scattered around

on the ground outside the hole. That's weird. It might make it look like the ants ate a live chicken or something, but that is not what happened. They appear to collect the feathers and put them there. Yeah, it kind of looks like there's a hole in the ground and like a bird was sucked down that hole. And if this is the cartoonish remnants of that incident, I thought the same thing. Yeah, I was like pop and then just puff of feathers they settle around it. But no,

that is not what has happened. The ants put the feathers there. Uh. Strange. So this paper published in twenty nineteen in in Ecological Anthropology, it claims that these feathers function as bait to attract prey animals, which then tumble into the nest entrance as if it were a pit trap. And the Scientific American article actually reports a bit of

the background on the paper. It says that the studies first author in Nacio Gomez, is an ecologist at the Federal University of Visosa and Brazil, and while walking around city parks and his college campus, he noticed examples of these ant nest entrances with feathers all around him. Apparently this had been observed before. And also I was looking

at another paper about this ant species. Finally oxy ops. Uh. This one was by Diego a cise at all from one and this paper said that in addition to feathers, there will sometimes be other objects around these nest and entrances, including shells, flower, pedals, and seeds. But this study in particular was was focusing on the feathers, and uh so, so he noticed these feathers around the entrances, and he

wondered was the deal with this? Apparently this had been observed before, and there were already a couple of untested hypotheses in the scientific literature about what the feathers were doing there. One idea was that the feathers could collect do in arid regions, so they would help provide the ants with water in the mornings. And the other idea was that somehow the feathers could serve as lures, attracting prey to the nest. And so the twenty nineteen study

tested both ideas. In one experiment, the researchers supplied the ant colonies with water soaked cotton balls, so made sure they had access to plenty of water, But the ants in these cases preferred to collect feathers anyway. It did not seem like access to water played any role in in their their desire to collect feathers, and this could be evidence that the feathers were not primarily for collecting water. But another test was designed to see if feathers scattered

on the ground would attract prey. So they tested this with artificial traps that were made to resemble the nest entrances of these ants, and the team found that if you put out a trap and scatter feathers around it, for some reason, it will tend to trap more just sort of uh, wanderers, you know, arthropods that are out on the ground than traps without feathers, And so interesting question, why would they do that. Why would a hole in the ground surrounded by feathers get more bugs to fall

into it. It's not known, but Gomez suggests that maybe it's something about the smell of the feathers, something about the visual appearance. Maybe a quote he gives to the Scientific American article, he says, just in general, soil insects are quote very curious. So maybe putting an unusual item around the entrance to the nest will just tend to get wandering bugs to walk up to it and see

if it's something of use to them. But I think this would not count just as baiting the way the way the burrowing out owl example, would with the how dung or the bison dung, because in this case it's not just to get the insects close to the nest. In this case, the actual nest entrances basically holes in the ground, function quite well as pit traps because once the prey insect falls in, they have difficulty climbing back out,

and the ants will rather quickly grab and butcher them. Now, this is clearly not the only way this ant species has to acquire prey. Fight only oxyops do leave the nest to acquire prey. They forage like other ant species.

But it's possible that using the nest as a pit trap and surrounding it with feathers as some kind of UH evolved behavior for luring more insects into the hole UH that helps the colony supplement their diet during especially times of the years, such as the dry season in this region, when prey is more scarce, harder to come by. So they wouldn't be obligate trap builders. They would they would be sort of they would have like a trap business on the side. I guess you would say, yes,

it is. If the trap interpretation is correct, it seems like this would be a supplemental role in getting extra food to them, extra diet diversity, especially in times when they're they're going to be getting less in their foraging, or maybe when they're doing less foraging. Okay, yeah, because there you know, again they're altering their immediate environment anyway. Um there so, and then again, a whole like this is not a huge energy investment. Um, the whole getting

already part of the nest. I guess the question is coming back to those those reasons that were put forth um earlier, that we don't see more pit traps. Does this would this make the the ant population more visible to potential predators? Um? I mean maybe maybe so, maybe not. Maybe maybe the animals that would be interested in eating the ants already would be able to detect their presence. And then again, also the ants have more capabilities than that one little larva at the bottom of a small pit.

You know, we're not dealing with one organism. We're dealing with this, um uh, this entire colony of organisms that that kind of behave as a single organism. Yeah, obviously, I don't I don't know what all the you know, the cost benefit analysis of of this evolutionary calculus would be um. But but yeah, there must be some reason why by having your aunt nest as a as a

pit trap in this environment. For this ant is is not such a it's not such a danger that it outweighs the benefit of getting some bugs to fall in as free meals. But I also like this because it's like by house analogy. It's like if your entire house was just like below the ground and the entrance to the house was a spike pit trap like a tiger trap, just waited for things to fall in and be like, oh bonus, here's dinner, and you alway, and the you

had the lures, you had the feathers all around. I don't know what that would be in the human example, you put just cotton candy around the around the trap that you come in through. Well, this is certainly another fascinating example. Um yeah, and I love how both present

the possibility of ants building traps. But since they are ants, like, it's it's not that cut and dry like like, ants have a complexity all their own, so you can't really look at them in the same way that you would look at a a single solitary spider or or certainly even the you know, the human example, Like what we do with traps and how we think about traps is a rather different scenario compared to anything, you know, anything

that we're seeing in in several of these animal examples. Yeah, well, I guess that does it for for ant traps on my end. But well, who knows what the future will hold. Perhaps there'll be more exciting studies coming out of the world of ant research. I mean, it's it's it's highly possible. I mean, we're still we're just still making a significant discoveries about about ant species and what they're up to. There are frontiers of ants you couldn't even dream of.

There are aunt traps that we don't even know about yet because they haven't been sprung on us when you fall into them. You go through the two thousand one stargate and in the in the room with the the French furniture. You know, we've never watched an ant movie for a weird house cinema. I wonder if we should at some point. Oh, I have for years been looking at the cover of a Blu ray at video drome called Phase four. It's a picture of a hand with some ants. I know it involves ants. I don't know

anything else. I guess that the question I would have, especially after talking about ants like this again, is are we looking at thinking about movies that that just that have a giant ant in them and have encounters with various giant ants, or is it truly about the ants as this kind of superorganism um and I like the ladder. Yeah, though, maybe having a giant sized ant is kind of a way through our fantastic fiction that we think about super organisms.

So it's kind of like, yes, the ants are small, but they they work together and they're able to do great things. So we just think of like a giant ant. That's like just one way of contemplating what they're capable of.

So the next time Aunt movies come back, if you're out there thinking about resurrecting the giant Aunt movie, consider having them like care people apart things like that, Um, you know, crawling out of windows, pulling people Taunt against the sides of a building and then transferring them up

to the rooftop and tearing them to pieces final processing. Yes, all right, well we're gonna go and close out this episode here, but we'd love to hear from everybody out there about traps, traps and movies, Traps in the human world, traps in the animal world. Um is there is there some corner of this topic you'd like for us to explore more in the future. Let us know we would

love to hear from you. If you would like to listen to other episod those of Stuff to Blow Your Mind, you will find them in the Stuff to Blow Your Mind podcasts. Feed core episodes on Tuesdays and Thursday's listener mail on Monday's short form artifact on Wednesdays. On Friday, we do weird how cinema. That's our time to set aside most serious concerns and just look at a strange film. As always, you can also get to us rather quickly by going to Stuff to Blow your Mind dot com.

Huge thanks as always to our excellent audio producer Seth Nicholas Johnson. If you would like to get in touch with us with feedback on this episode or any other to suggest topic for the future, just to say hello, you can email us at contact and Stuff to Blow your Mind dot com. Stuff to Blow Your Mind's production of I Heart Radio. For more podcasts for my Heart Radio usit the iHeart Radio app, Apple podcasts, or wherever you're listening to your favorite shows by pressing stop